Does Gisele Bundchen have another genetically superior bun baking in her oven? Her reps aren't commenting, but the rumor mill in her native Brazil is cranking with whispers that she may be expecting her second child with her coif-challenged, New England Patriots star hubby, Tom Brady.

Last week, the supermodel mogul was in Sao Paulo promoting her HOPE lingerie collection, and although she didn't give off a hint of any belly swelling while posing in a bra-showcasing lace shirt (below), insiders have supposedly been spilling the ostensible stork news, according to House of Models columnist Fabio Lage.

Brazilian paper Agora (via Brazil Dispatch) also claims "those responsible for dressing the model at recent events noticed changes in Gisele's body," which, granted, could mean she just had an extra serving of salad at lunch.

Bundchen, 31, is already mom to Benjamin, who made his debut in December 2009 via home delivery in a bathtub, and stepmom to Brady's 4-year-old son, Jack, with ex-girlfriend Bridget Moynahan.

The square-jawed twosome enjoyed a second honeymoon of sorts with a trip to Costa Rica in late February, not long after the Patriots lost the Super Bowl and Gisele was overheard griping of the quarterback's teammates, "My husband cannot [bleeping] throw the ball and catch the ball at the same time. I can't believe they dropped the ball so many times."

Bundchen has made no secret of her desire to expand her brood, and the family recently completed work on a $20 million, 22,000-square-foot estate in Brentwood, Calif.